533 



NOTE ON THE BACTERIOTOXIO ACTION OF WATER. 



By R. Greig-Smith, D.Sc, Macleay Bacteriologist to the 



Society. 



The presence of bodies, toxic to bacteria, have been known to 

 occur in water for some time, just as their existence in soils has 

 been suggested. Sidney Martin,* in 1900, showed that when 

 typhoid bacteria are added to a well moistened, cultivated soil, 

 they rapidly die out, and are not usualljr obtained two days 

 afterwards. The same occurs when the typhoid bacillus is added 

 to a culture of a soil-microbe in bouillon; it rapidly disappears. 

 Sidney Martin explained this phenomenon by the bacteria in 

 general being destroyed by the products of putrefaction^ which 

 exist in most cultivated soils. Referring to the growth of the 

 typhoid bacillus, he said that it cannot grow except in the 

 presence of organic matter containing nitrogen, and, on this 

 account, it grows for only a short time in sterilised distilled or 

 tap-water. That there is something more than the absence of 

 organic matter to explain its disappearance in sterilised water, 

 may be inferred from his experiment with the bouillon-culture of 

 the soil-bacillus. 



Typhoid bacteria rapidly disappear in sewage which contains 

 a certain amount of nitrogenous, organic matter. For example, 

 Houston! added 205 per 0*01 c.c. of sewage, and as he could 

 recover only 20, he concluded that the remainder had been 

 destroyed. 



With regard to the growth of bacteria in waters, Miguel,; in 

 1891, noted that a rapid, but transitory, increase occurred in 

 spring waters, while, in impure waters, the increase was slow but 



* Loc. Govt. Kept. 1900. Suppl., p. 487. 

 t Metrop. Water Board, Ninth Research Rept., through Journ. Soc. 

 Chem.Ind. 1913, 764. 



JFrankland, Micro-organisms in Water, Loudon, 1894. 



